Process for preparing beta-ethylenically unsaturated organic sulfonates



United States Patent Ofiice 3,346,629 Patented Oct. 10, 1967 PROCES FOR PREPARING BETA-ETH- YLENICALLY UNSATURATED ORGAN- IC SULFONATES George L. Broussalian, Overland, Mo., assignor to Monsanto Company, a corporation of Delaware No Drawing. Filed Aug. 15, 1963, Ser. No. 302,440

' 9 Claims. (Cl. 260513) This invention relates to new and useful detergent compositions and to processes for preparing them. More particularly, this invention relate-s to both aqueous and nonaqueous compositions which contain significant amounts of beta-ethylenically unsaturated organic sulfonate-type compounds that can be represented by Formula 1:

SOaM

wherein R and R are hydrophobic organic radicals containing from 1 to about 21 carbon atoms or hydrogen, the sum of the total number of carbon atoms in R plus R is from about 8 to about 21, and M is either hydrogen, an alkali metal cation, an alkaline earth metal cation, or an ammonium cation; and to processes for preparing these materials.

The swiftly increasing consumption of high foaming household hand dishwashing compositions over the past several years both in this country and abroad is conclusive evidence of the increasing value of this type of product both to manufacturers of such dishwashing compositions and to manufacturers of surface active agents (surfactants) that can be utilized in the formulation of such compositions. In view of the importance of this end use, a search for new and improved hand dishwashing detergents is being cond-ucted practically continuously by many surfactant manufacturers.

In order to qualify as a useful hand dishwashing surfactant, a material must have the ability to cause the formation of large quantities of foam or lather when aqueous solutions of the materials are agitated, which lather is stable when greases or greasy soils are also dissolved or dispersed therein. It has been discovered that when the above-described beta-ethylenically unsaturated sulfonate-type compounds are utilized in sufiicient amounts or proportions, either with or without other surfactants, in hand dishwas-hing compositions, for example, unexpectedly large quantities of foam or lather which is extremely stable in the presence of dissolved greases or greasy soils results therefrom. While extremely small amounts of some of the beta-ethylenically unsaturated sulfonates described above may inadvertently have been produced heretofore (in processes, for example, in which other types of surfactants were manufactured in very large quantities or proportions) the valuable benefits that result from using larger amounts were not appreciated heretofore.

It has now been discovered that not only are the abovedescribed beta-ethylenically unsaturated organic sulfonatetype compounds of this invention useful as general purpose surface active agents in aqueous solutions, but they are particularly useful as agents which produce unexpeotedly large quantities of foam or lather when they are dissolved in water, which foam or lather is extremely stable in the presence of dissolved and/or dispersed greases. Thus, the compositions of this invention represent particularly useful laundry and .dishwashing detergent compositions.

Ordinarily the organic radicals (designated by R and R in Formula 1, above) that are present in the betaethylenically unsaturated organic sulfonate-type compounds of the present invention can be branched or unbranched to practically any degree without substantially eliminating all of the benefits that can result from the invention. It is generally preferred, however, that the organic radical(s) be straight-chain in nature. It is still further preferred that the sum of the total number of carbon atoms in R and R be between about 9 and about 17. Although organic radicals R and R can contain heterocyclic, monocyclic hydrocarbyl, and polycyclic hydrocarbyl radicals (whether the rings are saturated or not), and can also contain substituents such as halides (including, for example, fluoride, chloride, bromide and iodide), ester groups, ether groups, thioe-ther groups, nitro groups, sulfone groups, sulfoxide groups, amide groups, nitroso groups, and the like, in their otherwise aliphatic or alicyclic radicals, it is preferred that R and/ or R be either hydrocarbyl in nature or that they contain only halide substituen-ts in their otherwise hydrocarbyl radicals. Also, it is particularly preferred that the sulfonate group (in the above-described beta-ethylenically unsaturated organic sulfonate-type compounds that are contemplated for use in the practice of this invention) be attached to the carbon atom which is at an end of a long chain hydrophobic organic radical (preferably alkyl, except for the double bond in the beta position), and that the single ethylenictype unsaturation appear between the second and third carbon atoms in the same long chain. For example, these particularly preferred compounds just described include those having a structure such as that illustrated in Formula 2:

( HHH wherein R is a higher alkyl radical, preferably containing from about 9 to about 17 carbon atoms, and M is an alkali metal cation. Of these compounds, those having straight chain alkyl groups are even further preferred.

While from the above discussion it can be seen that the alkali metal sulfonate salts are preferred forms of the above-described be-ta-ethylenica'lly unsaturated sulfonate-type compounds, it is nevertheless a fact that ammonium salts, as well as alkaline earth metal salts (where, for example, M in Formulas 1 and 2, above, represents /2Ca++, /z-M-g+ /2 Ba++, /2Sr++ or /2Ra+ can be used in the practice of this invention. Of the pre ferred alkali metal salts (including Li, Na, K, Rb, Cs, Fr) the sodium and potassium salts are particularly preferred, especially from the standpoint of cost.

Typical, but non-limiting examples of the beta-ethylenically unsaturated organic sulfonate-type compounds that are useful in the practice of the present invention include sodium Z-n-hexadecene-l-sulfonate, sodium 12-bromo-2- n-dodecene-l-sulfonate, magnesium Z-n-tetradecene-l-sulfonate sodium 9,10-dichloro-2-n-octadecene-l-sulfonate, potassium Z-(branched) pentadecene-l-sulfonate, sodium 9 methoxy 2 n octadecene 1 sulfonate, ammonium 2-n-octadecene-l-sulfonate, sodium l-(p-n-dodecylphenyl)1-propene-3-sulfonate, sodium 2-n-pentadecene-3-sulfonate, sodium 3- (p-n-tetradecylphenyl 1-propene-3 -sulfonate, potassium 1-hydroxy-3-n-heptadecene-Z-sulfonat, lithium 2-n-octadecene-4-sulfonate, ammonium l-n-hexadecene-Z-sulfonate, calcium 1-acetoxy-3-n-heptadecene-2- sulfonate, potassium 1Z-methylmercapto-2-dodecene-l-sulfonate, sodium l-(branched, from propylene) tridecene-2- sulfonate, sodium 2,9-n-octadecadiene-l-sulfonate, potassium 9,10-epoxy-Z-n-octadecene-l-sulfonate, sodium l-noctadecene-3-sulfonate, sodium 4-n-hexadecene-3-sulfonate, potassium l-(B-napthyl)-1-propene-3-sulfonate, sodium Z-n-hexaiodooctadecene-l-sulfonate, sodium ll-car- ,boethoxy-Z-n-dodecene-l-sulfonate, sodium ll-carbamido- 2-n-dodecene-1-sulfonate, potassium 2-n-pentadecene-1- sulfonate, sodium 2,-n-octadecene-l-sulfonate, sodium 6-noctadecene-S-sulfonate, sodium 1-cyclohexyl-1-n-pentadecene-3-sulfonate, sodium 10-nitroso-2,S-n-octadecadienel-sulfonate, and the like.

Some of the beta-ethylenically unsaturated organic sulfonate-type compounds to which the present invention relates can be manufactured starting with an appropriate carboxylic acid which is ethylenically unsaturated at a 2- position (with reference to the carboxyl group) by first reducing the carboxylic acid group to the corresponding alcohol or OH group with a reducing agent such as lithium aluminum hydride in a suitable solvent such as anhydrous ether. The resulting ethylenically unsaturated alcohol can then be converted to the corresponding bromide (where Br replaces the OH group by reacting the alcohol under anhydrous conditions with phosphorus tribromide). The resulting ethylenically unsaturated bromide can then be converted to the corresponding ethylenically unsaturated sulfonic acid via sulfitation, for example by refluxing the bromide at atmospheric pressure in the presence of sodium bisulfite, methanol, and water. Subsequent neutralization of the resulting sulfonic acid then yields the more generally useful 2-ethylenically unsaturated-l-sulfonate compound.

Another process for manufacturing these desired betaethylenically unsaturated organic sulfonate-type compounds involves the sulfonation of an appropriate monoolefinic, hydrophobic organic compound with sulfur trioxide under circumstances in which it is believed that initially the formation of a beta-sultone such as that illustrated in Formula 3:

(3) H H H RCOO-R O-SO2 wherein R and R have the same meaning as they have in Formula 1; above, is favored, followed by the controlled rearrangement of the beta-sultone to the corresponding beta-ethylenically unsaturated organic sulfonic acid;

This sulfonic acid is then neutralized with an appropriate base if and when desired to yield one of the abovedescribed sulfonates. This monoolefin-beta sultone route for manufacturing the desired beta-ethylenically unsaturated organic sulfonate-type materials described above is a considerably less expensive method than that process described immediately above (involving the use of an un saturated carboxylic acid as a starting material). Consequently, the unsaturated-SO process constitutes a particularly preferred embodiment of the present invention.

In order to encourage the formation of beta-sultone rather than the formation of substantial amounts of other products such as carbyl sulfates and the like (which ordinarily cannot be utilized advantageously in the manufacture of the beta-ethylenically unsaturated organic sulfonate-type compounds of the present invention), it has been found that the sulfonation of the monoolefinic raw material should be carried out at a temperature below about 10 C., and preferably at a temperature below about 5 C. In addition, while it is not essential, it is preferred that the monoolefinic material be dissolved in an inert (to S0 neutral, anhydrous solvent during the sulfonation step in order to minimize polymerization and/or degradation of the monoolefinic material in the presence of S0 Since it is believed that the fraction of the initially formed beta-sultone which remains soluble in the sulfon ation solvent thereby also remains more subject to further reaction with S0 to form the undesired carbyl sulfate, it is particularly preferred that the neutral solvent that is utilized in the sulfonation step of any of the processes of this invention be one in which the betasultone is soluble at most to the extent of about 20 weight percent. The neutral solvents referred to herein are neutral in the Lewis acid-base sense and include such a solvents as pentane, isopentane, hexane, heptane, isoheptane, octane, isooctane cyclopentane, cyclohexane, 2,2,4- trimethylpentane, 2,2-dimethylbutane, methylcyclohexane, petroleum ether petroleum benzine, naptha, ligroin, kerosene, gasoline, decalin, turpentine, methylene chloride, methylene bromide, chloroform, carbon tetrachloride, butyl chloride, ethyl bromide, ethylene dichloride, ethylene dibromide, ethylidene chloride, ethylene chlorobromide, tetrafluoroethane, ethylene trichloride, tetra-bromoethane, propylene dichloride, and the like. The presence of basic or acidic solvents, whether polar or non-polar, in excessive amounts (i.e., over about two moles of basic or acidic solvent per mole of olefinic raw material) should generally be avoided during the sulfonation step of these preferred processes because of the tendency of the presence of such excessive amounts of acidic or basic solvents (at this stage) to enhance the formation of undesirable carbyl sulfates and/or other by-products that cannot readily be converted to the desired beta-ethylenically unsaturated sulfonate or sulfonic acid compounds of the present invention.

Carbyl sulfates are illustrated in Formula 4, below:

(4) H H H wer SOz-O The term basic solvent is herein intended in the Lewis base sense, wherein the solvent compound contains at least one oxygen or sulfur atom, for example, in its molecule which oxygen or sulfur atom has available two electrons which can facilitate the abstraction of a proton from a compound such as the above-described beta-sultone. Typical non-limiting examples of such basic solvents include ethyl ether, isopropyl ether, dioxane, ethyl thioether, triethyl phosphate, ethyl acetate, organic nitrates such as n-hexyl-1-nitrate, isopropyl acetate, ethyl sulfate, thioxane, carbon disulfide, and the like. It is preferred, too, that the solvents that are used in these processes be substantially aprotic (i.e., do not contain active hydrogens) since such aprotic materials (such as amines, nitriles, acids, and the like) react with the betasultone to yield addition products which differ substantially from the beta-unsaturated sulfonates of the present invention.

During the sulfonation step of these preferred processes, it is also preferred that the molar ratio of sulfur trioxide to monoolefinic raw material that are reacted together he at most about 1.5 :1, respectively, and preferably between about 0.95 :1 and about 1.05:1, respectively, in order to minimize the formation of undesired by-products, including carbyl sulfates, which ultimately form less desirable sulfonate materials than those of the present invention; although generally the molar ratio should be at least about 0.2: 1.

It is surprisingly advantageous, after the beta-sultone has been formed, to actually perform the next (reorganization) step of these preferred processes in the presence of one or more basic solvents, such as those described hereinbefore. While the presence 10f even a small amount of basic solvent during the reorganization stage or step of these preferred processes (i.e., even as little as 0.1 mole or less of basic solvent per mole of SO -olefinic reaction product) is helpful in this respect, preferably fairly large quantities such as more than 2 moles of one or more basic solvents per mole of betasultone that is made should be utilized for highest yields of the desired beta-unsaturated sulfonate compounds of this invention. Any amounts of basic solvent above this level can be utilized, but as a practical matter, generally the use of not more than about moles of basic solvent per mole of S0 that reacted with the olefinic raw material is recommended. Of all of the basic solvents, ethyl ether and dioxane are particularly preferred for use during this stage of these preferred processes. Thus, it has been discovered that when the beta-sultones described above are warmed to above about 15 C., and preferably to a temperature above about 20 C., the beta-sultone rearranges to the corresponding beta-ethylenically unsaturated organic sulfonic acid:

and when such warming is permitted or performed with the beta-sultone in physical contact with more than 2 moles of one or more basic solvents per mole of sultone (or SO -olefin reaction product), the desired rearrangement is greatly enhanced. For example, when the betasultone of l-n-hexadecene is warmed from -20 C. to 15 C. over a period of 30 minutes while the sultone is in a neutral solvent such as ethylene dichloride, only about weight percent of the desired beta-ethylenically unsaturated material is formed. By comparison, when the beta-sultone of n-hexadecene is first dissolved in ethyl ether and then allowed to Warm in the same manner, 70 weight percent of the desired beta-ethylenically unsaturated compound is formed.

Complexes of sulfur trioxide that tend to attenuate the reactivity of S0 can also be utilized advantageously in these preferred processes. Complexes that do not contain a nitrogen atom are generally preferred, however, because in some instances, unless great care is taken, the use of complexes of S0 with a nitrogen-containing compound such as pyridine, organic nitrile, and the like result in the reaction of the nitrogen-containing compound with the sultone with concomitant production of byproducts, rather than the desired beta-ethylenically unsaturated compound of this invention.

Actually, the desired beta-ethylenically unsaturated organic sulfonate-type compositions of the present invention can also be manufactured by sulfonating an appropriate mono-ethylenically unsaturated compound with sulfur trioxide and without apparently manufacturing a significant or noticeable amount of the beta-sultone intermediate when the unsaturate-SO reaction is carried out at or above about 0 C. provided several precautions are observed. However, carrying out the reaction at temperatures above about C. is generally not recommended because at these relatively high temperatures, side reactions (other than that desired) occur; generally the higher the temperature the greater the proportion of the undesired materials produced with consequently much lower yields of the desired beta-ethylenically unsaturated sulfonate.

Manipulative procedures for sulfonating ethylenically unsaturated compounds with sulfur trioxide are wellknown in the art and need not be detailed here. Any particular manipulative procedure desired can be utilized in the practice of the processes of this invention so long as the above-described precautions are observed.

One of the preferred processes of this invention involves the controlled reaction of sulfur trioxide with the raw monoolefin material in such a way as to prevent the interreaction of more than about 1.2 moles of S0 per mole of the monoolefin. The proper control of this reaction can be accomplished in several ways. For example, about one molar proportion of sulfur trioxide can first be reacted with about one molar proportion of a complexing agent such as dioxane, if desired, in a non-basic solvent such as ethylene dichloride (at a very low temperature) to form a complex of S0 with dioxane. Then about one molar proportion of the monoolefin is added rapidly to the resulting mixture. By intermixing the olefin rapidly into the solvent-complex mixture, localized excesses of the complex (i.e., much more than about 1.221 'ratio of complex to olefin at a given small area in the resulting mixture) are minimized. The resulting mixture can then be stirred for several minutes, or until the sulfonation reaction is completed to the desired extent, and the sulfonated product (largely beta-sultone) can then be warmed to room temperature. For even better results, at least several moles of additional dioxane (or some other basic solvent) can be added to the cold reaction product before it is warmed significantly above about 15 C.

Another procedure for controlling the amount of S0 that reacts with the above-described monoolefinic raw materials involves initially the dissolution of the olefin in a non-basic, inert (to S0 solvent such as n-hexane and then adding sulfur trioxide slowly to the cooled solution or partial dispersion of the olefin in the solvent (which solvent can also contain a small amount of one of the above-described desirable complexing agents). After about one mole of S0 per mole of olefin has been introduced into the cold reaction medium, the resulting reaction product can be allowed to warm to room temperature.

The beta-ethylenically unsaturated sulfonate-type compounds that are useful in the practice of the present invention can be utilized advantageously as general purpose detergent active ingredients either alone or in combination with practically any material than can be employed in combination with known organic detergent anionic and nonionic surface active agents, such as soap, the alkali metal fatty alcohol sulfates, the alkali metal, ammonium, and alkaline earth metal alkylaryl sulfonates; higher alcohol-ethylene oxide condensates, alkylphenolethylene oxide condensation products, fatty acid-ethylene oxide condensation products, for example, sodium dodecylbenzene sulfonate; and other similar surfactants. The types of materials that than can be employed in the formulation of socalled polyphosphate built detergents, liquid heavyduty detergents, light-duty detergents, flake and powdered compositions (presuming the usual consideration of compatibility are applied), include such materials as other organic anionic and/ or nonionic and/ or ampholytic surface active agents or materials, polyphosphate complexing agents and other inorganic and organic builders, antiredeposition agents, optical brightener, bleaching agents, and the like; all of which are well-known in the detergent art and need not be detailed here. It is interesting to note that the beta-ethylenically unsaturated sulfonate-type materials of this invention can be utilized advantageously in practically any of the compositions in which the alkylaryl sulfonates, for example, can be utilized. It should be noted, however, that whenever these beta-ethylenically unsaturated sulfonates are utilized in combination with other organic surface-active agents such as the higher alkyl benzene sulfonates, for example; generally in order for the unexpectedly desirable properties of the beta-ethylenically unsaturated sulfonate to become readily apparent when the mixture or combination of organic surfactants is ultimately dissolved in water, the amount of the beta-ethylenically unsaturated sulfonatein the organic surfactant combination should be at least about 10 weight percent, based on the total combined weight of the organic surfactants in the combination. Preferably, this proportion of the beta-ethylenically unsaturated sulfonate should be at least about 15 weight percent of the total amount of organic detergent surface active ingredients in any aqueous or non-aqueous composition in which they are utilized.

The beta-ethylenically unsaturated sulfonates described above are particularly useful when they are formulated into so-c-alled built detergent compositions and used as such, for example, as light duty or heavy duty laundering detergents. Built detergents are those that contain, in addition to the detergent active material, at least one water-soluble inorganic builder salt such as an alkali metal pyrophosphate, tripolyphosphate, carbonate, sulfate, or the like. In such built detergent compositions, the outvention can readily be appreciated when the composition contains at least about weight percent, and up to about 50 weight percent or more; preferably from about to about 35 weight percent; of these beta-ethylenically unsaturated sulfonate (s).

As it was stated hereinbefore, the beta-ethylenically unsaturated sulfonates described above can advantageously be utilized along with any other anionic, nonionic, or ampholytic detergent active materials (surfactants) or mixtures thereof in the proportions specified above. The term anionic surfactants, encompasses such materials as the alkali metal salts of fatty acids and fatty acid derivatives, commonly known as soaps (such as sodium laurate, sodium palmitate, and the potassium salts of coconut fatty acids); the alkali metal salts of sulfuric esters [such as sodium lauryl alcohol sulfate, potassium hexadecanol sulfate, lithium petroleum alcohol (average C chain length) sulfate as well as the alkali metal sulfates of condensation products of alcohols containing from about 10 to about 30 carbon atoms with from about 2 to about 40 moles of a lower alkylene oxide such as ethylene oxide, propylene oxide, or mixtures thereof]; the alkali metal salts of alkanesulfonates, preferably straightchain alkanesulfonates (such as those prepared by sulfonating certain petroleum fractions with S0 the alkali metal and alkaline earth metal salts of esterand etherlinked sulfonates [such as the sodium dialkyl sulfosuccinates (wherein alkyl contains from about 4 to about 20 carbon atoms), the potassium lauryl diester of 2,3-dihydroxypropane-l-sulfonate] amide-linked sulfonates (such as sodium oleylmethyltaurate, sodium 4-acyl-aminobutane-l-sulfonates, and sodium myristyl sulfomethylamide); alkylarylsulfonates wherein the single alkyl group preferably contains from about 10 to about 20 carbon atoms (such as sodium dodecylbenzene sulfonate); mahogany and petroleum sulfonates; and the like. The term nonionic surfactants encompasses such materials as the condensation products of several moles of a lower alkylene oxide such as ethylene-, propylene-, or butylene-oxide with a mole of a higher alkyl alcohol, alkylphenol, fatty acid, and the like (wherein the alkyl group contains from about 10 to about 20 or more carbon atoms); the fatty alkanolarnides (such as the diethanolamide of tall oil fatty acids and the diethanolamide of lauric acid); and the polyhydroxy nonionic surfactants (such as sorbitol monolaurate, and the reaction products of fatty primary amines with delta-gluconolactone). The ampholytic surfactants contain both acidic and basic functional groups in their individual molecules, and include such materials as dodecyl-beta-alanine, sodium Ndodecyl taurate, and the products from reacting benzene amino sulfonic acid, for example, with n-hexadecylchloride. Other examples of organic anionic, nonionic and ampholytic surfactants that can also be present in compositions containing the betaethylenically unsaturated sulfonate materials described above can be found in Surface Active Agents and Detergents, by Schwartz et al., Interscience Publishers, Inc., New York (1958), volume II.

The pure beta-ethylenically unsaturated sulfonate compounds of this invention as well as compositions containing them such as those described above, have physical and chemical properties that make them particularly outstanding detergents for use in the form of aqueous solutions (containing them) to clean various solid substrates in the presence of dissolved and dispersed greases, for example, as a hand dishwashing detergent composition. In a standard test designed to closely examine the suitability of various water-soluble surface active agents for use in the formulation of high foaming hand dishwashing detergents, sodium Z-n-hexadecene-l-sulfonate cleaned more than 20 plates before the foam or lather on the surface of the test solution broke, while sodium dodecylbenzene sulfonate (made from a tetrapropylene olefin) effectively washed only about 8 plates before the lather broke when it was used in the same test under practically identical conditions. These high-foaming beneficial properties of the beta-ethylenically unsaturated sulfonates of this invention can be readily appreciated when these materials are present (dissolved) in water at a level of at least about 0.005 weight percent (so that they represent at least about 10 weight percent of the total surfactant therein). For optimum results, this level should be generally between about 0.010 and about 20 weight percent, and preferably between about 0.015 and about 10 weight percent of the total aqueous solution weight.

In the following example, which is illustrative of one of the preferred embodiments of this invention, all parts are by weight unless otherwise specified.

EXAMPLE I Process Into a conventional glass-lined reaction vessel fitted with a fairly efficient stirrer are poured 1000 parts of ethylene dichloride, 88 parts of dioxane, and 224 parts of n-hexadecene-l. The resulting solution is then cooled to a temperature of about 20 C. Then, with constant agitation, a total of 88 parts of sulfur trioxide in the gaseous form (preblended with an equal volume of dry nitrogen) are introduced into the bottom of the reaction vessel gradually over a period of about 120 minutes. As the reaction progresses, the desired beta-sultone is observed crystallizing out of solution. After the addition of sulfur trioxide gas is completed, the resulting reaction product (almost entirely the beta-sultone dispersed in a mixture of ethylene dichloride and dioxane) is further diluted with 200 parts of dioxane, and then warmed slowly (over a period of about 60 minutes) to room temperature. During this warming, the insoluble beta-sultone gradually disappears.

The resulting solution of Z-n-hexadecene-l-sulfonic acid is then neutralized with about parts of a 50 weight percent aqueous solution of sodium hydroxide. Subsequent distillation of the solvent mixture at about 15 C. at a pressure of about 20 mm.-Hg yields a residue containing about 80 weight percent of the desired sodium 2-n-hexadecene-1-sulfonate. The remainder is a mixture of unreacted n-hexadecene-l, and by-products sodium hydroxy-n-hexadecane-l-sulfonate, l-n-hexadecene-l-sulfonate, and a very small amount of other unidentified material.

Relatively pure sodium 2-n-hexadecene-l-sulfonate can be isolated from this mixture by simply extracting the mixture with methanol and filtering to remove the hydroxy sulfonates. Then the methanol solution can be concentrated to a small volume by distilling off the methanol. After most of the methanol is removed and the concentrated product cooled to about room temperature a precipitate of the product, sodium 2-n-hexadecene-l-sulfonate, is formed. However, the residue (after removal of the solvent mixture) from Example I is itself an excellent very high foaming surfactant; yielding an extremely high volume of foam when it is dissolved in water at a level of about 0.1 weight percent and the water is subsequently agitated, which foam is unexpectedly stable in the presence of dissolved greases, as for example, after many greasy dishes are washed in the aqueous solution.

From Example I, above, it is evident that, rather than extremely pure beta-ethylenically unsaturated sulfonate or sulfonic acid products, the products resulting directly from the preferred processes of the present invention are almost invariably mixtures containing, in addition to a fairly large proportion of the desired beta-ethylenically unsaturated material some hydroxy sulfonate and some alpha-ethylenically unsaturated materials. These latter two classes of materials (actually by-products from the present processes) are generally somewhat poorer surfactants than are the beta-ethylenically unsaturated materials. However, because it is presently commercially uneconomical to separate these by-products from the more desirable materials, the form in which the beta-ethylenically unsaturated sulfonic acids and sulfonates of the pres ent invention will most likely be sold and utilized for and in the practice of the present invention is in admixture with such other aliphatic sulfonates. The particular sulfonates which are in admixture with a particular betaethylenically unsaturated sulfonate will depend upon the particular raw monoolefinic material from which they were manufactured, as well as the particular conditions observed and practiced during the sulfonation and reorganization steps of the processes of this invention. While beneficial mixtures of aliphatic sulfonates (which for the foregoing reasons constitute preferred embodiments of the present invention) as little as about 15 weight percent of the beta-ethylenically unsaturated sulfonates, generally the beta-ethylenically unsaturated sulfonates should be present in the mixtures in an amount larger than that in which any of the other (alpha-unsaturated, or Z-hydroxy) sulfonates are present therein. For optimum results; in so far as high lather in aqueous solutions and excellent lather stability in the presence of greasy soils, as well as other valuable surfactant properties, are concerned; generally such preferred mixtures of aliphatic sulfonates should contain at least about 50 weight percent, and preferably at least about 80 weight percent of the beta-ethylenically unsaturated sulfonates.

A procedure such as that described in Example I, above, can be utilized to manufacture any of the betaethylenically unsaturated sulfonates useful in the practice of the present invention. This can be accomplished simply by substituting appropriate mono-ethylenically unsaturated starting materials for reaction with sulfur trioxide, and subsequently neutralizing the resulting sulfonic acid with an appropriate base.

For the sake of convenience and more ready understanding of the aforementioned fundamentals of the present invention, the beta-ethylenically unsaturated organic sulfonate-type compounds of this invention have generally been referred to as though they were pure components, containing for example hydrophobic radicals, alkyl groups, and the like (as R and R is Formulae 1 and 2) which are all identical. It is well known by those skilled in the art, however, that a high degree of purity in such compounds is very rarely if ever attainable in practical commercial operations for manufacturing detergents. Thus, in practice when a particular chain length such as dodecyl, hexadecene, octadecene, and the like are referred to, almost invariably these terms mean that these are the average chain lengths in the particular surfactant materials being described, and that, in addition to dodecyl, for example, some chain lengths varying to some extent from C in length can be (and generally are) present therein. Similarly, where terms are utilized herein referring to a particular chain length such as hexadecene, tetradecene, and the like, it is intended that this be about the average chain length, and that the term encompass mixtures of materials having chain lengths varying to some extent from the named average chain length. It is generally preferred, however, that such mixtures of materials contain at most about 10 weight percent of materials varying more than about 3 carbon atoms on either side of the named average. For example, the term sodium 2-n-hexadecene-l-sulfonate includes not only the pure hexadecene material but also mixtures containing from about tridecene to about nonadecene wherein the average chain length of the mixture is C and less than a total of 10 Weight percent of the materials in the mixtures have chain lengths less than C or more than C Generally, in such mixtures, material containing the named average number of carbon atoms will be the largest single component in the mixtures.

Table 1, below, illustrates the valuable benefits which can be obtained when the preferred beta-ethylenically unsaturated sulfonates of this invention are utilized as laundering detergents.

10 TABLE 1.-DETERGENCY DATA? Compound: Detergency (a) Sodium 2-n-alkylene-1-sulfonate (average (b) Potassium 2 (branched)alkylene-l-sulfonate (average C (c) Sodium 9 methoxy 2-n-alkylene-1-sulfonate (average C 108 (d) Potassium 1 hydroxy-3-n-alkylene-2-sulfonate (average C (e) Ammonium 1 n alkylene 3 sulfonate (average C 121 (f) Calcium 1 acetoxy-3-n-alkylene-2-sulfonate (average C 95 (g) Sodium 3 n hexachloroalkylene-S-sulfonate (average C 102 (h) Sodium 1 cyclohexyl 1 n pentadecene- 3-sulfonate 98 (i) Potassium 2 n tetradecene-l-sulfonate (j) Sodium (p n dodecylphenyl)-1-propene- 3 sulfonate 111 (k) Lithium 7 n butoxy-2-n-alkylene (average C )-1-sulfonate 105 (1) Sodium 12 bromo 2 n dodecene-l-sulfonate 108 1 300 p.p.m. hard water. Test described by Jay C. Harris in gilaflltluaition of Surface Active Agents, ASTM Bulletin, May

Table 2, below, illustrates the very valuable benefits that can be obtained by utilizing these materials as hand dishwashing detergents both alone and in combination with other surface active agents. Details on the test procedure for evaluating hand dishwashing detergents are described after Table 2.

TABLE 2.EVALUATION A-S HA ND DISHWASHING DETERGENTS Composition: Plates washed (m) Control 1 8 (n) Sodium 2 n alkylene-l-sulfonate (average C16) (0) Potassium 2 n alkylene-l-sulfonate (average C 15 (p) Ammonium 2 n alkylene-l-sulfonate (average C 18 (q) Sodium 2 (branched) alkylene-4-sulfonate (average C 15 (r) 50 sodium 2 n alkylene-l-sulfonate (average C 50 sodium (tetrapropylene)dodecylbenzene sulfonate 18 (s) 50 sodium 2 n alkylene-l-sulfonate (average C 50 sodium lauryl sulfonate 20 (t) 50 sodium 2 n hexadecene-l-sulfonate, 50

dodecylphenol+10 (ethylene oxide) 2 14 (u) 20 sodium 2 n hexadecene-l-sulfonate, 80

sodium (tetrapropylene)dodecylbenzene sulfonate 14 (v) Sodium-1-n-pentadecene-3-sulfonate 16 1 Sodium dodecylbenzene sulfonate made from tetrapropylene average C12 alkyl group.

2 Product from reaction product of alkylphenol with about 10 moles of ethylene oxide per mole of alkylphenol, (Alkyl: C12 average.)

This hand dishwashing test involves the washing by hand of nine-inch dinner plates which are pre-soiled with one teaspoonful each of a synthetic soil mixture consisting of 75 Weight percent of shortening and 25 weight percent of flour. Washing of the plates is performed (using a dishcloth to remove the synthetic soil) in 4 liters of Water having an initial temperature of about 50 C. and containing 0.075 weight percent of the surfactant or surfactant mixture being tested. The number of plates washed is determined by the number of plates which can be cleaned in the normal fashion by the time the lather on the surface of the dishpan has broken to the extent that less than half of the surface remains covered with lather. The manipulative procedures of this test are described in greater detail in the Proceedings of the 43rd Annual Meeting of the Chemical Specialties Manufacturers Association, December 1956; Procedure No. 3, page 191.

In the following Table 3 are tabulated data showing some typical surfactant properties of one of the outstanding preferred -betaethylenically unsaturated sulfonates of the present invention (practically pure sodium-Z-hexadecene-l-sulfonate) TABLE 3.-SURFACTANT EVALUATION DATA 1 In 300 p.p.m. hard water. Test described by Jay C. Harris in Evaluation of Surface Active Agents, ASTM Bulletin, May, 1946.

2 50 C. values taken 5 minutes after lather was formed.

3 Room temperature, in distilled water.

What is claimed is: 1. A process for preparing a compound of the formula wherein R and R in each instance are selected from the group consisting of hydrogen, alkyl radicals and halogen, lower alkoxy, phenyl, hydroxy, methyl mercapto, naphthyl, epoxy acetoxy, carboethoxy, carbamido, nitroso, and cyclohexyl substituted al'kyl radicals, the total number of carbon atoms in R plus R being from about 8 to about 21, and wherein M is selected from the group consisting of hydrogen, alkali metal cations, alkaline earth metal cations, and ammonium cations, which comprises reacting together in a neutral, in the Lewis acid-base sense, solvent and at a temperature below about C. (a) a monoolefinically unsaturated organic compound containing one double bond, said double bond connecting two adjacent carbon atoms, and a third carbon atom connected directly to one of said two adjacent carbon atoms; said third carbon atom having attached thereto at least two hydrogen atoms, said compound containing a total of form about 11 to about 24 carbon atoms, and said compound being selected from the group consisting of olefins and substituted olefins having substituents selected from the group consisting of halogen, lower alkoxy, phenyl, hydroxy, methyl mercapto, naphthyl, epoxy, acetoxy, carboethoxy, carbamido, nitroso, and cyclohexyl substituents; with (b) at most about 1.5 moles of sulfur trioxide per mole of said compound; diluting the resulting reaction product with a basic, in the Lewis base sense, solvent; and then raising the temperature of the resulting diluted reaction product above about C.

2. A process as in claim 1, wherein said monoolefinically unsaturated organic compound is a mixture of olefins having an average chain length of from about 12 to about 20 carbon atoms; said olefins being reacted with said sulfur trioxide at a temperature below about 5 C.

3. A process as in claim 2, wherein said olefins are alphaolefins.

4. A process as in claim 3, wherein said alpha-olefins are nalpha-olefins.

5. A process for preparing a compound of the formula wherein R is an alkyl radical containing from about 9 to about 17 carbon atoms and M represents an alkali metal cation which comprises forming a beta-sultone by reacting together in an anhydrous, neutral, in the Lewis acidbase sense, inert solvent system at a temperature below about 5 C. (a) one molar proportion of an alphaolefin containing from about 12 to about 20 carbon atoms and having a methylene group next adjacent to the carbon atom which is connected to the end carbon atom in said olefin by the double bond with (b) from about 0.95 to about 1.05 molar proportions of sulfur trioxide; said solvent system containing at most about 2 molecular proportions of a basic, in the Lewis base sense, solvent and said solvent system being one in which said ,B-sultone is soluble at most to the extent of 20 weight percent; subsequently, after most of said beta-sultone has been formed, adding more than two moles of basic solvent per mole of said beta-sultone to said solvent system, and then raising the temperature of said beta-sultone to above about 20 C.

6. A process as in claim 5, wherein said alpha-olefin is a mixture of alpha-olefins having an average of from about 12 to about 20 carbon atoms.

7. A process as in claim 6, wherein said basic solvent is dioxane.

8. A process as in claim 7, wherein said alpha-olefins are n-alpha-olefins and have an average chain length of about 16 carbon atoms.

9. A process according to claim 5 wherein said anhydrous solvent system comprises ethylene dichloride as the principal solvent.

References Cited RICHARD K. JACKSON, Primary Examiner.

ALBERT T. MEYERS, Examiner.

M. WEBSTER, Assistant Examiner. 

1. A PROCESS FOR PREPARING A COMPOUND OF THE FORMULA 